contactAngle BC in contactAngleCavity tutorial is not working as expected

Summary

In the tutorial case contactAngleCavity, the free surface of a cavity is simulated with the interfaceTrackingFvMesh library. In the simulation a contact angle of 70° is set at the walls via the file 0.orig/contactAngle. The contact angle after running the tutorial, however, is ~80°.

Steps to reproduce

Copy the case $FOAM_TUTORIALS/incompressible/pimpleFoam/laminar/contactAngleCavity
Add the following function objects for post-processing (this writes out the first two and last two points on the free surface):

   pointHistoryLeft1
    {
        type            pointHistory;
        refHistoryPoint (0 0.01 0);
        fileName        leftPoint.txt;
    }
    pointHistoryLeft2
    {
        type            pointHistory;
        refHistoryPoint (0.00025 0.01 0);
        fileName        leftPointRef.txt;
    }
    pointHistoryRight1
    {
        type            pointHistory;
        refHistoryPoint (0.01 0.01 0);
        fileName        rightPoint.txt;
    }
    pointHistoryRight2
    {
        type            pointHistory;
        refHistoryPoint (0.00975 0.01 0);
        fileName        rightPointRef.txt;
    }

Calculate the angle between the first two and the last two points respectively. This can be done by running the accompanied script postProcessing.py inside the simulation directory.

Example case

I attached the tutorial case with slight modifications in the functionObjects, together with the post-processing script. Run the case using the Allrun script.

contactAngleCavity.tar

What is the current bug behaviour?

The contact angle at the specified locations is not equal to the set contact angle.

What is the expected correct behavior?

The contact angle should be 70°, as specified in 0.orig/contactAngle.

Relevant logs and/or images

The Figure below shows the calculated angle between the first two and the last two mesh points. Note that the angle does not change with a longer run time. The tutorial runs only for 0.2s.

Environment information

OpenFOAM version : v2212

Operating system : ubuntu docker container on windows

Possible fixes

The calculations regarding the contact angle can be found in the file $FOAM_SRC/dynamicFaMesh/interfaceTrackingFvMesh/freeSurfacePointDisplacement.C in lines 120-197. In this approach, the vector N is rotated by the value of contactAngle at the specified boundaries. The patchMirrorPoints at this boundary are then moved using (line 225f.):

patchMirrorPoints[patchI] =
            peCentres + ((I - 2*N*N)&delta);

Maybe the innermost controlPoints have to be moved as well to satisfy the contact angle.

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